|This article is about a/an evil mecha in Choudenshi Bioman.|
Sonic Megas (ソニックメガス Sonikkumegasu, 39) is a Neo Mecha-Gigan of Neo Empire Gear, piloted by Bio Hunter Silva.
A Neo Mecha-Gigan with a pair of sonic emitters to disrupt electronics, can fly, and can launch missiles from its hands.
Sonic Megas is a Neo Mecha-Gigan given to Silva by Gear in their claim that it had the means to help him find his missing mecha, Balzion. When Silva traces nearby Bio Particles, he tracks them down in this mecha, with Bioman following until they become trapped by multiple supersonic devices meant to harm the electronics within both the Super-Electronic Brains of Bioman and Silva's circuitry. After Bioman destroys the trap with the help of Hikaru's flute playing and throwing Psygorn into one of the disruptors with Super Electron, Silva faces them once again with the Neo Mecha-Gigan, but it is easily defeated by Bio Robo.
- In a surprising twist, Sonic Megas is the only mecha this season that is solely piloted by Bio Hunter Silva; even his own Balzion is actually shared at one point with Farrah piloting it in an episode.